1. Field of Invention
The present invention relates to eyeglasses and more particularly to such a pair of eyeglasses adapted to lockingly engage with a detachable auxiliary eyeglass frame.
2. Related Art
Eyeglasses adapted to engage with an auxiliary eyeglass frame are well known. Conventionally, the main eyeglasses have a recess in its either endpiece and the auxiliary eyeglass frame has a tab also in its either endpiece. The tabs are adapted to engage with the recesses by snapping.
However, the prior art suffered from a couple of disadvantages. For example, the snapping engagement is not reliable, resulting in a possible disengagement of the tabs and the recesses especially after a period time of use. Further, alignment of either pair of the tab and the recess is required to be precise. Otherwise, the desired engagement of the tab and the recess in either pair is not possible. This in turn may require a high precision in the manufacturing process. As a result, the manufacturing cost is increased significantly. This is not desirable in this competitive market. Thus, a need for improvement exists.